Constant rate of strain consolidation testing of soft clays and fibrous peats

The constant rate of strain (CRS) oedometer test, using an imposed vertical strain rate (epsilon) over dot(I) equal to 10 times the end-of-primary (EOP) vertical strain rate (epsilon) over dot(p), requiring a test duration of about 2 days produces reliable information on both the e versus log sigma(v)' relation and e versus logk(v) relation of soft clays and fibrous peats. An empirical correction for the strain rate effect on preconsolidation pressure leads to the EOP e versus log sigma(v)' relation and EOP sigma(p)'. The imposed vertical strain rate (epsilon) over dot produces excess pore-water pressures at the impervious bottom of the specimen, corresponding to u(b)'/sigma(v) values in the range of 3%-15% and allows, use of the Darcy flow equation, a reliable calculation of the coefficient of permeability. Compressibility and permeability data are from CRS and incremental loading (IL) oedometer tests on specimen quality designation (SQD) A samples of seven soft clays and two fibrous peats are presented in this paper.